/Engine/Plugins/Runtime/GeometryProcessing/Source/DynamicMesh/Public/Operations/GroupTopologyDeformer.h
Solving Update TargetMesh by first calling HandleVertexDeformFunc() to get new handle vertex positions, then solving for new ROI vertex positions.
virtual void UpdateSolution ( [FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) * TargetMesh, const [TFunction](API\Runtime\Core\GenericPlatform\TFunction)< FVector3d([FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) *[Mesh](API\Plugins\DynamicMesh\Operations\FGroupTopologyDeformer\Mesh), int)> & HandleVertexDeformFunc )